CN109164159B - Method and device for measuring bubble flow parameters of gas-solid fluidized bed - Google Patents
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Abstract
The invention discloses a method and a device for measuring bubble flow parameters of a gas-solid fluidized bed, wherein the method comprises the following steps: an electrostatic sensor array is adopted to obtain electrostatic signals generated by bubble flow in the fluidized bed, the electrostatic signals are converted, filtered and amplified through a preposed signal conditioning module, the processed signals are transmitted to a computer through a data acquisition card, and real-time online measurement of bubble flow parameters is realized by combining cross correlation function operation and peak searching Gu Suanfa; the device comprises an electrostatic sensor array, a preposed signal conditioning module, a data acquisition card and a computer which are electrically connected in sequence. The invention has the advantages of high reliability, low cost, safety and the like, can realize real-time online measurement, and is suitable for severe industrial field conditions.
Description
Technical Field
The invention belongs to the technical field of measurement of bubble flow parameters in a fluidized bed, and particularly relates to a method and a device for measuring bubble flow parameters of a gas-solid fluidized bed.
Background
The fluidized bed technology is widely applied to the fields of chemical industry, petrochemical industry, metallurgy, energy, materials, biochemistry, environmental protection, pharmacy and the like at present, and compared with the traditional combustion and reaction equipment, the fluidized bed has the advantages of high heat and mass transfer efficiency, easy control of bed temperature, easy feeding and discharging of bed materials, easy control and adjustment of reaction process, capability of improving the yield of products and the like. The phenomenon of bubbles is the most basic characteristic of a gas-solid fluidized bed, and the existence of the bubbles not only has an effect on the hydrodynamic property in the bed, but also has obvious influence on the gas-solid mixing, mass transfer and heat transfer performance in the bed. Therefore, the deep understanding of the flow characteristics of bubbles is an important basis for researching a gas-solid fluidized bed and is also an important premise for understanding the flow and fluidization quality in the bed. The study on the flow characteristics of bubbles in a fluidized bed mainly involves measuring the rising speed and diameter of the bubbles. The rising speed of the bubbles is one of important parameters of the bubbles, and the size of the bubbles determines the turbulence intensity in the bed and the contact quality of gas-solid two phases; the size of the bubble diameter directly affects the mixing quality of the gas-solid medium in the bed. The larger the diameter of the bubbles is, the faster the speed of the bubbles is, more gas flows through the bed layer through the bubbles, and the mixing of gas and solid media is poor, so that the gas-solid phase reaction is not facilitated; conversely, when the bubbles are smaller, the gas velocity in the bed is generally lower, the mobility of the medium is insufficient, and the mixing of gas and solid materials is also not facilitated. Therefore, in the case of intensive studies on gas-solid fluidized beds, measurement of the rising speed and diameter of bubbles is particularly important.
The techniques for measuring bubble parameters can be mainly categorized into two types: one is a contact method such as a probe method, a differential pressure method, etc.; the other is non-contact method such as chromatography, photography, etc.
Among the methods for studying the characteristics of bubbles, the image measurement method using a probe method and a high-speed camera is two measurement methods widely used in the field of measurement of bubble parameters in a fluidized bed in recent years. The measuring principle of the probe method is to realize the measurement of bubble parameters in a fluidized bed by utilizing the physical property difference between different phases, such as conductivity, refractive index, reflectivity and the like, and the method has the defects of easy abrasion of a probe, complicated installation process and the like in a gas-solid fluidized bed, so that the method is mainly used for measuring the bubble parameters in gas-liquid two phases. The measurement method based on the high-speed camera is characterized in that the bubbles are continuously photographed, the photographed images are processed by combining an image processing algorithm to obtain the rising speed, the diameter and other data of the bubbles, the method is limited to a transparent fluidized bed, the photographed images are required to be subjected to subsequent processing, the measurement delay is high, and the method is only suitable for theoretical research on a laboratory scale and is not suitable for an industrial field fluidized bed device.
Disclosure of Invention
The invention aims at solving the problems in the prior art and provides a method and a device for measuring the flow parameters of bubbles in a gas-solid fluidized bed, wherein a plurality of groups of electrostatic sensor arrays are arranged in the fluidized bed, when the bubbles flow through the electrostatic sensor arrays, the output signals of the groups of arrays are subjected to cross-correlation operation to obtain the flow speed of the bubbles, and then the diameters of the bubbles are calculated according to the time when the bubbles flow through the electrostatic sensors; the invention has the advantages of high reliability, low cost, safety and the like, can realize real-time online measurement, and is suitable for severe industrial field conditions.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a method for measuring the flow parameters of bubbles of a gas-solid fluidized bed comprises the following steps:
s1, adopting an invasive electrostatic sensor, wherein each two electrostatic sensors form an array, and a plurality of groups of arrays are uniformly arranged in a fluidized bed;
s2, performing cross correlation operation on electrostatic signals generated by bubble flow obtained by an electrostatic sensor, and calculating the flow speed of bubbles;
s3, filtering the measured signals by adopting a filtering algorithm to remove noise interference; processing the filtered electrostatic signal by a peak and valley searching algorithm, and calculating the time of bubbles flowing through the electrostatic sensor;
and S4, calculating the diameter of the air bubble according to the air bubble flowing speed and the time of the air bubble flowing through the electrostatic sensor.
Specifically, when the bubbles pass through the fluidized bed from bottom to top, electrostatic signals are generated on the electrodes of the electrostatic sensor.
Specifically, in step S1, two electrostatic sensors of the one array are arranged on the wall surface of the fluidized bed in a vertical direction, a distance between the two electrostatic sensors is fixed, and in the same array, the electrostatic sensor located above is an upstream electrostatic sensor, and the electrostatic sensor located below is a downstream electrostatic sensor.
Specifically, in step S2, the electrostatic signals obtained by the electrostatic sensors are converted into voltage signals through a signal conversion circuit, and then local upstream electrostatic signals and downstream electrostatic signals in each group of electrostatic sensor arrays are collected through a data collection card; the cross-correlation function of the signals measured by each group of electrostatic sensor arrays is expressed as:
wherein R (τ) is a cross correlation function of the delay time τ, T is the sampling time, x (T) is the upstream electrostatic signal, and y (T- τ) is the downstream electrostatic signal; the flow rate of the bubbles is:
v＝L/τ m
wherein L is the center distance between an upstream electrostatic sensor and a downstream electrostatic sensor, and τ m Is the time for a bubble to pass through a set of electrostatic sensor arrays.
Specifically, in step S3, the filtering algorithm is a moving average filtering method;
further, in the gas-solid fluidized bed, if a single bubble passes through the electrostatic sensor, the time Δt for the bubble to flow through the electrostatic sensor is:
Δt＝t max -t min
wherein ,tmax The wave crest moment in the voltage signal output by the electrostatic sensor electrode is represented, namely, the moment when the bottom of the bubble just leaves the electrostatic sensor electrode; t is t min The wave trough moment in the voltage signal output by the electrostatic sensor electrode is represented, namely, the moment when the top of the bubble just contacts the electrostatic sensor electrode;
further, if a plurality of bubbles flow through the electrostatic sensor at the same time in the gas-solid fluidized bed, the voltage signal output by the electrostatic sensor electrode generates superposition of a plurality of wave crests and wave troughs, the filtered electrostatic signal is processed by adopting a wave crest and wave trough searching algorithm, and after the superposed wave crest and wave troughs are removed, the time of the adjacent wave troughs and wave crest time differences are calculated, so that the time of the single bubble flowing through the electrostatic sensor can be obtained; average time of bubble group passing through electrostatic sensorThe method comprises the following steps:
wherein N is the number of bubbles flowing through one electrostatic sensor in the sampling time T, delta T k Indicating the time it takes for the kth bubble to flow through the electrostatic sensor.
Specifically, in step S4, the diameter of the air bubble is calculated by the following method:
inside the gas-solid fluidized bed, if a single bubble passes through the electrostatic sensor, the diameter of the single bubble is:
D＝v·Δt
wherein v is the flow velocity of the single bubble, Δt is the time the single bubble flows through the electrostatic sensor;
if a plurality of bubbles simultaneously flow through the electrostatic sensor, the average diameter of the bubble group flowing through the electrostatic sensor in the time T is as follows:
v'＝L/τ' m
wherein v' is the velocity of the bubble group flowing through the electrostatic sensor,for the average time of bubble group passing through electrostatic sensor, τ' m Is the time for a bubble group to pass through a set of electrostatic sensor arrays.
A gas-solid fluidized bed bubble flow parameter measurement device, comprising:
the electrostatic sensor arrays are used for acquiring electrostatic signals generated in the process of bubble flow in the gas-solid fluidized bed;
the preposed signal conditioning module is used for converting the electrostatic signal into a voltage signal and performing filtering and amplifying treatment;
the data acquisition card is used for acquiring the voltage signals processed by the pre-signal conditioning module;
the computer is used for analyzing and storing the voltage signals acquired by the data acquisition card;
the input ends of the plurality of groups of electrostatic sensor arrays and the preposed signal conditioning modules are connected through electrostatic signal transmission cables, the output ends of the preposed signal conditioning modules and the input ends of the data acquisition cards are connected through 37pin D-Sub transmission lines, and the output ends of the data acquisition cards and the computers are connected through USB transmission lines.
Specifically, the pre-signal conditioning module comprises a signal conversion circuit, a filter circuit and an amplifying circuit; the signal conversion circuit is used for converting the electrostatic signals acquired by the electrostatic sensor into voltage signals, the filtering circuit is used for filtering the converted voltage signals to eliminate noise interference, and the amplifying circuit is used for amplifying the filtered voltage signals so as to facilitate the data acquisition card to acquire the filtered voltage signals.
Specifically, a data acquisition circuit is embedded in the data acquisition card and is used for acquiring the voltage signal processed by the pre-signal conditioning module.
Compared with the prior art, the invention has the beneficial effects that: (1) According to the invention, the electrostatic sensor array is arranged in the fluidized bed to detect electrostatic signals generated in the rising process of bubbles, and the electrostatic signals are processed to realize real-time online measurement of bubble parameters, so that the method has high timeliness and high accuracy; (2) Compared with the traditional high-speed camera bubble parameter measurement method, the method can be applied to complex non-transparent industrial fluidized beds, and has wider application range; (3) The measuring device has the advantages of simple structure, easy installation, maintenance and disassembly and low cost.
Drawings
FIG. 1 is a schematic block diagram of a method for measuring bubble flow parameters of a gas-solid fluidized bed in example 1;
FIG. 2 is a schematic diagram showing the overall structure of a bubble flow parameter measuring apparatus for a gas-solid fluidized bed according to example 2;
FIG. 3 is a raw signal obtained by the electrostatic sensor in example 1;
FIG. 4 is the voltage signal after filtering in example 1;
FIG. 5 is a graph showing the change in voltage signal of a single bubble flowing through an electrostatic sensor in example 1;
FIG. 6a is a schematic diagram of the top of the bubble just contacting the electrostatic sensor electrode in example 1;
FIG. 6b is a schematic diagram of bubbles passing through the electrostatic sensor electrode in example 1;
FIG. 6c is a schematic view of the bottom of the bubble just leaving the electrostatic sensor electrode in example 1;
FIG. 7 is a flowchart showing the voltage signal processing in the embodiment 1;
in the figure: 1. air bubbles; 2. an electrostatic sensor; 3. a fluidized bed wall; 4. an electrostatic signal transmission cable; 5. a pre-signal conditioning module; 6. 37pin D-Sub transmission line; 7. a data acquisition card; 8. a USB transmission line; 9. and a computer.
Detailed Description
The following description of the embodiments of the present invention will be made more apparent and fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by one of ordinary skill in the art without undue burden on the person of ordinary skill in the art based on embodiments of the present invention, are within the scope of the present invention.
Example 1
As shown in fig. 1, the embodiment provides a method for measuring a bubble flow parameter of a gas-solid fluidized bed, which includes the following steps:
s1, adopting invasive electrostatic sensors 2, forming an array by every two electrostatic sensors 2, and uniformly arranging a plurality of groups of arrays in a fluidized bed;
s2, performing cross correlation operation on electrostatic signals generated by the flow of the bubbles 1 obtained by the electrostatic sensor 2, and calculating the flow speed of the bubbles 1;
s3, filtering the measured signals by adopting a filtering algorithm to remove noise interference; processing the filtered electrostatic signals by a peak and valley searching algorithm, and calculating the time of the bubbles 1 flowing through the electrostatic sensor 2;
s4, calculating the diameter of the bubble 1 according to the flow speed of the bubble 1 and the time of the bubble 1 flowing through the electrostatic sensor 2.
Specifically, in the gas-solid fluidized bed, the flow of the bubbles 1 can cause electrostatic change, the electrostatic change signal is sensed by the electrostatic sensor 2 and converted into a voltage signal by the pre-conditioning circuit, the voltage signal is collected by the data collection card 7 after filtering and amplifying treatment, and finally the voltage signal is transmitted to the computer 9, and the real-time online measurement of the flow parameters of the bubbles 1 is realized by combining the operation of the cross correlation function and the peak searching Gu Suanfa.
Specifically, in step S1, two electrostatic sensors 2 of the one array are arranged on the wall surface 3 of the fluidized bed in a vertical direction, a distance between the two electrostatic sensors 2 is a fixed L, and in the same array, the electrostatic sensor 2 located above is an upstream electrostatic sensor, and the electrostatic sensor 2 located below is a downstream electrostatic sensor.
Specifically, in step S2, the electrostatic signals obtained by the electrostatic sensors 2 are converted into voltage signals by a signal conversion circuit, and after being processed by a filter circuit and an amplifying circuit, the data acquisition card 7 is used to acquire local upstream electrostatic signals (x 1 (t)，x 2 (t)，…，x n (t)) and downstream electrostatic signal (y) 1 (t)，y 2 (t)，…，y n (t)) performing acquisition; the cross-correlation function of the signals measured by each group of arrays of electrostatic sensors 2 is expressed as:
wherein R (τ) is a cross correlation function of the delay time τ, T is the sampling time, x (T) is the upstream electrostatic signal, and y (T- τ) is the downstream electrostatic signal; the flow speed of the bubbles 1 is as follows:
v＝L/τ m
wherein L is the center-to-center distance of the upstream and downstream electrostatic sensors 2, τ m For bubbles 1 through a set of arrays of electrostatic sensors 2Is a time of (a) to be used.
Specifically, in step S3, the filtering algorithm is a moving average filtering method;
further, in the gas-solid fluidized bed, when the bubbles 1 flow through the electrode of the electrostatic sensor 2, the change of the voltage signal output by the electrostatic sensor 2 is shown in fig. 3, the signal is obviously burred due to the interference of background noise, the obtained voltage signal is filtered by adopting a moving average filtering method, the noise interference is removed, and the filtered voltage signal is shown in fig. 4;
in the gas-solid fluidized bed, if a single bubble 1 passes through the electrostatic sensor 2, the voltage signal output by the electrode of the electrostatic sensor 2 will have a trough and a crest as shown in fig. 5, wherein the trough is at a moment t min Indicating that the bubble 1 just entered the electrode, at which time the top of the bubble 1 just contacted the electrode, as shown in fig. 6 a; time t of peak max Indicating that the bottom of the bubble 1 just leaves the electrode as shown in fig. 6 c; the middle trough-to-peak period represents the process of bubble 1 passing through the electrode, as shown in fig. 6b, with the electrode in the middle of bubble 1; the time Δt for the bubble 1 to flow through the electrostatic sensor 2 is:
Δt＝t max -t min
when the fluidized bed is in a natural bubbling state, the continuous flow of the bubble group passes through the electrostatic sensor 2, and the voltage signal continuously generates wave peaks and wave troughs, as shown in fig. 3, if a plurality of bubbles 1 simultaneously flow through the sensor, the voltage signal can generate superposition of a plurality of wave peaks and wave troughs; in order to calculate the time of a single bubble 1 passing through the sensor, a wave crest and wave trough searching algorithm is adopted to process the electrostatic signal after filtering, the processing flow is shown in figure 7, after overlapping wave crests and wave troughs are removed, the time difference between adjacent wave troughs and wave crests is calculated, and the time of the single bubble 1 passing through the electrostatic sensor 2 can be obtained; if N pairs of adjacent trough and crest signals coexist in the sampling time T, the condition that N bubbles 1 flow through a certain electrostatic sensor 2 in the sampling time T is indicated; average time of bubble group passing through electrostatic sensor 2The method comprises the following steps:
wherein N is the number of bubbles 1 flowing through one electrostatic sensor 2 within a sampling time T, Δt k Indicating the time taken for the kth bubble 1 to flow through said electrostatic sensor 2.
Specifically, in step S4, the diameter of the air bubble 1 is calculated by the following method:
inside the gas-solid fluidized bed, if a single bubble 1 passes through the electrostatic sensor 2, the diameter of the single bubble 1 is:
D＝v·Δt
where v is the flow velocity of the single bubble 1, Δt is the time the single bubble 1 flows through the electrostatic sensor 2;
if a plurality of bubbles 1 flow through the electrostatic sensor 2 at the same time, the average diameter of the bubble group flowing through the electrostatic sensor 2 in the T time is:
v'＝L/τ' m
wherein v' is the velocity of the bubble group flowing through the electrostatic sensor 2,for the average time of the bubble group passing through the electrostatic sensor 2, τ' m Is the time for a group of bubbles to pass through the array of electrostatic sensors 2.
The embodiment adopts the array electrostatic sensor and combines the corresponding signal processing method to realize the real-time on-line measurement of the flow parameters of the bubbles in the gas-solid fluidized bed, overcomes the limitation that the high-speed camera method is only suitable for experimental study of the two-dimensional transparent fluidized bed, and can be used for on-line monitoring of the flow conditions of the bubbles in the complex industrial fluidized bed.
Example 2
As shown in fig. 2, the present embodiment provides a device for measuring a bubble flow parameter of a gas-solid fluidized bed, including:
the electrostatic sensor 2 arrays are used for acquiring electrostatic signals generated in the flowing process of the bubbles 1 in the gas-solid fluidized bed;
the preposed signal conditioning module 5 is used for converting the electrostatic signal into a voltage signal and performing filtering and amplifying treatment;
the data acquisition card 7 is used for acquiring the voltage signals processed by the pre-signal conditioning module 5;
the computer 9 is used for analyzing and storing the voltage signals acquired by the data acquisition card 7;
the array of the plurality of groups of electrostatic sensors 2 is connected with the input end of the preposed signal conditioning module 5 through an electrostatic signal transmission cable 4, the output end of the preposed signal conditioning module 5 is connected with the input end of the data acquisition card 7 through a 37pin D-Sub transmission line 6, and the output end of the data acquisition card 7 is connected with the computer 9 through a USB transmission line 8.
Specifically, the pre-signal conditioning module 5 includes a signal conversion circuit, a filter circuit, and an amplifying circuit; the signal conversion circuit is used for converting the electrostatic signal acquired by the electrostatic sensor 2 into a voltage signal, the filtering circuit is used for filtering the converted voltage signal to eliminate noise interference, and the amplifying circuit is used for amplifying the filtered voltage signal so as to facilitate the data acquisition card 7 to acquire.
Specifically, a data acquisition circuit is embedded in the data acquisition card 7 and is used for acquiring the voltage signal processed by the preamble signal conditioning module 5.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (2)
1. The method for measuring the bubble flow parameters of the gas-solid fluidized bed is realized based on a device for measuring the bubble flow parameters of the gas-solid fluidized bed, and is characterized by comprising the following steps:
the multi-group invasive electrostatic sensor array is used for acquiring electrostatic signals generated in the process of bubble flow in the gas-solid fluidized bed;
the preposed signal conditioning module is used for converting the electrostatic signal into a voltage signal and performing filtering and amplifying treatment; the pre-signal conditioning module comprises a signal conversion circuit, a filter circuit and an amplifying circuit;
the data acquisition card is used for acquiring the voltage signals processed by the pre-signal conditioning module; a data acquisition circuit is embedded in the data acquisition card;
the computer is used for analyzing and storing the voltage signals acquired by the data acquisition card;
the input ends of the plurality of groups of invasive electrostatic sensor arrays are connected with the input ends of the preposed signal conditioning modules through electrostatic signal transmission cables, the output ends of the preposed signal conditioning modules are connected with the input ends of the data acquisition cards through 37pin D-Sub transmission lines, and the output ends of the data acquisition cards are connected with the computer through USB transmission lines;
the measuring method comprises the following steps:
s1, adopting an invasive electrostatic sensor, wherein each two invasive electrostatic sensors form an array, and a plurality of groups of arrays are uniformly arranged in a fluidized bed;
s2, performing cross correlation operation on electrostatic signals generated by bubble flow obtained by the invasive electrostatic sensor, and calculating to obtain the flow speed of the bubbles; the electrostatic signals obtained by the invasive electrostatic sensors are converted into voltage signals through a signal conversion circuit, and then the local upstream electrostatic signals and the local downstream electrostatic signals in each group of invasive electrostatic sensor arrays are collected through a data collection card; the cross-correlation function of the signals measured by each set of invasive electrostatic sensor arrays is expressed as:
；
wherein ,is delay time->T is the sampling time, x (T) is the upstream electrostatic signal, +.>Is a downstream electrostatic signal; the flow rate of the bubbles is:
；
wherein L is the center-to-center distance between the upstream and downstream invasive electrostatic sensors,time for a bubble to pass through a set of invasive electrostatic sensor arrays;
s3, filtering the measured signals by adopting a filtering algorithm to remove noise interference; processing the filtered electrostatic signals by a peak and valley searching algorithm, and calculating the time of bubbles flowing through an invasive electrostatic sensor; the filtering algorithm is a moving average filtering method;
in the gas-solid fluidized bed, if a single bubble passes through the invasive electrostatic sensor, the time for the bubble to flow through the electrostatic sensorThe method comprises the following steps:
；
wherein ,tmax The wave crest moment in the voltage signal output by the invasive electrostatic sensor electrode is represented, namely, the moment when the bottom of the bubble just leaves the invasive electrostatic sensor electrode; t is t min Indicating the moment of the trough in the voltage signal output by the invasive electrostatic sensor electrode, i.e. the bubble top just touching the invasive electrostatic sensorThe moment of the electrical sensor electrode;
if a plurality of bubbles flow through the invasive electrostatic sensor at the same time in the gas-solid fluidized bed, the voltage signal output by the electrode of the invasive electrostatic sensor generates superposition of a plurality of wave crests and wave troughs, the wave crest and wave trough searching algorithm is adopted to process the filtered electrostatic signal, and after the superposition of the wave crests and wave troughs are removed, the time difference between the adjacent wave troughs and wave crests is calculated to obtain the time of the single bubble flowing through the invasive electrostatic sensor; the average time for the bubble group to pass through the invasive electrostatic sensor is:
；
wherein N is the number of bubbles flowing through an invasive electrostatic sensor during the sampling time T,indicating the time taken for the kth bubble to flow through the invasive electrostatic sensor;
s4, calculating the diameter of the air bubble according to the air bubble flowing speed and the time of the air bubble flowing through the invasive electrostatic sensor; the diameter of the bubbles was calculated as follows:
inside the gas-solid fluidized bed, if a single bubble passes through the invasive electrostatic sensor, the diameter of the single bubble is:
；
wherein v is the flow velocity of the single bubble,the time for the single bubble to flow past the invasive electrostatic sensor;
if a plurality of bubbles simultaneously flow through the invasive electrostatic sensor, the average diameter of the bubble group flowing through the invasive electrostatic sensor in the time T is as follows:
；
；
wherein v' is the velocity of the bubble group flowing through the invasive electrostatic sensor,mean time for bubble group to pass through invasive electrostatic sensor, +.>Is the time for a bubble group to pass through a set of invasive electrostatic sensor arrays.
2. The method according to claim 1, wherein in the step S1, two invasive electrostatic sensors of the one array are arranged on the wall surface of the fluidized bed in a vertical direction, a distance between the two invasive electrostatic sensors is fixed, and in the same array, the invasive electrostatic sensor located above is an upstream invasive electrostatic sensor, and the invasive electrostatic sensor located below is a downstream invasive electrostatic sensor.
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| CN109902760B (en) * | 2019-03-18 | 2020-10-27 | 中国石油大学(北京) | Two-dimensional bubble identification method in gas-solid bubbling bed |
| CN110296912B (en) * | 2019-06-19 | 2020-07-21 | 北京理工大学 | System and method for detecting dust cloud cluster diffusion dynamic turbulent flow energy based on ultrasound |
| CN110530920A (en) * | 2019-10-15 | 2019-12-03 | 苏州原位芯片科技有限责任公司 | Bubble detecting sensor device |
| CN113298011A (en) * | 2021-06-07 | 2021-08-24 | 中国矿业大学 | Method for identifying pressure fluctuation signal caused by bubbles in gas-solid fluidized bed |
| CN113522743B (en) * | 2021-07-30 | 2022-05-17 | 中国矿业大学 | Method and system for weakening bubbles in gas-solid separation fluidized bed |
| CN114966097B (en) * | 2022-04-26 | 2023-06-20 | 东南大学 | System and method for measuring flue gas flow velocity field based on invasive electrostatic sensor array |
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